Blade construction for carry-type scraper



Dec. 5, 1961 J. E. RICHTER 3,011,274

BLADE CONSTRUCTION FOR CARRY-TYPE SCRAPER Fi led Feb. 19, 1958 2 Sheets-Sheet 1 FlE J o o o 6 o 0 o INVENTOR.

John E F/c/ner Dec. 5, 1961 J. E. RICHTER BLADE CONSTRUCTION FOR CARRY-TYPE SCRAPER Filed Feb. 19, 1958 F'IE E.

2 Sheets-Sheet 2 INVENTOR.

Y John E. Q/c/v/er B ATTORNEY! 3,011,274 BLADE CONSTRUCTION FOR CARRY-TYPE SCRAPER John E. Richter, San Jose, Calif., as'signor, by mesne assignments', to Curtiss-Wright Corporation, South Bend,

Filed Feb. '19, 1958, Ser. No. 716,216 1 Claim. (Cl. 37-141) This invention relates generally toearth moving equipment of the type utilizing an earth digging or scraping bladetogether with a bowl or like structure for receiving or carrying a load to a point of discharge. More particularly, it relates to earth moving equipment making use of a main bowl having a forward digging blade, and having means for varying the cutting angle and loading characteristics of said blade, as necessary for different conditions of soil and loading.

The object of the present invention is to provide equipment of the above character having improved means for mounting the forward digging blade on the main bowl.

Another object of the invention is to provide an improved means of the. above character which readily permits variations in the cutting angle and loading characteristics of the digging blade, yet which is sufi'iciently rugged and durable to withstand conditions of loading and wear normally encountered.

Additional objects and advantages-of the invention will appear from the following description in'which the preferred embodiment has been'set forth in detail inconjunction with the accompanying drawing.

Referring to the'drawi'ng:

FIGURE 1 is a side elevation, partly in section, illustrating a machine incorporating the present invention.

FIGURE 2 is a top plan view illustrating the improved digging blade and its mounting base. 7

, base or mounting structure of unusual strength and mg FIGURE 3 is a view in transverse section along the line 33 of FIGURE 2.

FIGURE 4 is a like view along the line 4-4 of FIG- URE 2.

FIGURE 5 is a detail view in plan illustrating the blade mounting base having positioned thereon adjusting means in accordance with the invention.

In general, my machine consists of a main bowl A, in conjunction with a front load retaining portion or apron B, aframe structure C carried by the wheels, and an adjustable digging blade assembly D attached to a forward edge of themain bowl. Hydraulic or cable hoist means (FIGURE 1) are normally provided for raisin-g the frontapron and lowering the main bowl to a digging position as illustrated in FIGURE 1, and for raising the bowl and lowering the apron to permit carrying of the load after the digging operation is completed. I

The main bowl includes the sidewalls 10 (FIGURE 1). The forward portions of the sidewalls 10 are connected by the beam 12 which forms a convenient mounting base for the blade assembly D. The beam 12 can be reinforced by a rear plate member 14 and by a forward plate member 16, the latter presenting a forward inclined face 18 adapted to support the cutting blade.

As is best illustrated in FIGURE 5, the plate 16 of the blade base can be constructed with a central portion 17 of increased width. This portion of the plate is preferably provided with two rows of bolt apertures, the row 19 lying below a main row 20 which extends the entire length of the plate. Desirably the overhanging forward edge of the plate 16 is supported and reinforced by means of the bracing plates 22 positioned beneath end portions 23 and by larger plates 24 positioned beneath the central portion 17. As is evident from the drawings, the rigidly welded unit comprising beam 12, plates 14 and 16, and

the cross bracing members 22 and 24 provides a bladegedness.

It is contemplated that a digging blade 30 can be removably attached to the plate 16 by bolts or similar securing means 31 extending through the row of apertures 32 in the'blade, and through the aperturesv 20 of the bladebase. Preferably the blade Tall-comprises a plurality'of separate sections, in this case three sections,; including the end sections 34 and the central section 36. Preferably the central section 36 is of greater width than'the end sections and is provided with a second row of bolt aper-' tures 38, corresponding to the row 19 of the blade base. It will be understood that this construction permits a digging and loading action commencing with the central blade section 36 and spreading sideways to the end blade sections 34. i

It is a feature of the invention that reversible wedge elements are provided to permit a variation of the cutting angle and loading characteristics of the digging blade 30 as may be necessary in varying soil conditions or under varying conditions of loading. Preferably separate wedge elements are provided, such elements corresponding in dimension to the separate blade sections 34 and 36. Thus,

as illustrated in FIGURES 3 to 5 the end wedge ele-. ments 40 areoflesser width than thecentral faces or surfaces 44 and 46 disposed at a slight angle qt to one another so as to provide a thickened edge 50 (FIGURES 3 and 4). Although this angle qt will vary somewhat depending upon the particular type of earth moving equipment, it should not exceed about 10 nor. be less than about 3 In the illustrated apparatus, the

angle included betwen the faces 44 and 46 is preferably about 5, this angle having been found the most adaptable to operating conditions normally encountered.

As will be apparent from FIGURES 3 and 4, the

wedge elements 40 and 42- permit a substantial variation in the cutting angle of the blade 30, without in any way detracting from the overall strength and ruggedness of the blade assembly. Thus, in the full line positions of these figures, the wedge elements are positioned with their thickened edges 50 in a foremost position so that the cutting angle of the blade 30 is raised about 5 from a normal cutting angle. The dotted line positions illustrate a reverse position of the wedge elements in which their thickened edges 50 are in a rearmost position, and spaced from the cutting edge of the blade 30. This latter position lowers the cutting edge about 5 below its normal position or about 10 below the full line position. By way of example, the cutting angle of the illustrated apparatus can be varied from a normal angle of about 38 to a deeper cutting angle of 43, and to a shallower cutting angle of 33.

It is to be noted (FIGURES 3 and 4) that the upper surface presented by the three sections of the cutting blade 30 can be substantially planar regardless of the particular cutting angle employed. This is because of a transverse shifting of the center wedge element 42 made possible by the added row of bolt apertures 43. As will be apparent from a study of the full and dotted line positions of FIGURE 4, the center row of apertures 43 always corresponds with the upper rows 20 and 32 of the' "r' r 3,011,274, Patented Dec. 5, 1961 wedgeelement 42, and, are provided with a single row of boltis determined in accordance with the particular soil condition and operating requirements. For example, in a dry, sandy soil, the wedge elements would be set for a deep cutting angle as illustrated in the dotted line positions of FIGURES 3 and 4. Under such conditions, the cutting angle is sufiicient to keep the bowl hoists taut, and to permit a desired forced loading through the material to the rear of the bowl. With a shallower cutting angle, floating or skidding of the bowl might occur with consequent undesirable tensioning and slackening of the hoist lines. In contrast, if a very wet clay or similar soil were being encountered, the wedge elements would be positioned to provide a shallower cutting angle than normal, for example, as in the full line positions of FIG- URES 1, 3 and 4. The shallower cutting angle would permit proper loading Without overburdening of the hoists, or excess load reaction on thewheels of the tractor or carrier units.

From the above description it will be apparent that the present invention provides a digging assembly which makes possible optimum loading and digging characteristics under varying operating conditions.v The blade assembly of the invention not only can be varied in accordance with conditions of soil and loading, but maintains the necessary ruggedness and durability of construction necessary for forced loading, as in scraper carriers, and in general renders equipment employing such assemblies capable of withstanding the severe services to which earth movers and similar equipment are commonly subjected.

To those skilled in the art to which the present invention relates, many variations and widely differing appli cations and embodiments of the invention will suggest themselves without departing from the spirit and-scope hereof. For example, although illustrated as constructed in several parts, it will be understood that the blade and wedge units might be constructed as integral units without detracting from the usefulness of the blade assembly. Accordingly it should be understood that the disclosures and description herein are purely illustrative and not intended to be in any sense limiting.

I claim:

In earth moving equipment of the type including a wheeled frame and a main bowl carried by the frame, the bowl having a forward digging blade and adapted to be moved over the ground to takeon a load, means for varying the cutting angle and loading characteristics of said blade as necessary due to variations in soil and loading conditions, said'means comprising; a blade-base extending transversely of said main bowl and attached,

to a forward edge thereof, said blade base including a T-frame and plate member presenting a forward inclined face, said plate member being wider adjacent central portions than at endportions thereof, earth cutting blade means removably secured to said plate member and including a centrally disposed cutting blade having a pair of cutting blades disposed one on each side thereof, said centrally disposed cutting blade being wider than the other of said blades and adapted to extend further below the forward edge of said bowl as secured to said plate.

member, reversible wedge means received under each of said blades and being of relatively comparable length thereto, the centrally disposed of said wedge means being wider than the others thereof and extending over the wider central portion of said plate member, means for securing said blades to said plate member and said wedge means therebetween, said wedge means being cooperatively formed and collectively usable, removable and re versible for variably positioning said cutting blades at selected cutting angles and in contiguous planar relation.

References Cited in the file of this patent UNITED STATES PATENTS 348,242 Sawyer Aug. 31, 1886 1,674,110 Harden June 19, 1928 2,329,831 Ferguson Sept. 21, 1943' 2,729,001 Adams Jan. 3, 1956 2,778,129 Fryer Jan. 22, 1957 2,888,758 Allin June 2, 1959 FOREIGN PATENTS 22,883 Finland Dec. 1, 1949 

